FA UNA OF DE VONIA N FORMA TION A T MIL IV A UKEE 277 



Hall, all of which were probably determined from imperfect casts, 

 or may have been taken from erratic blocks wrongly supposed to 

 have been derived from this formation. Others, like Spirifer 

 granuliferus Hall, 5. audaculus Conrad, 5. angustus Hall, and 5. 

 euryteines, var. fomaculus Hall, were probably mistaken identifica- 

 tions, justified at the time, but based upon casts of Spirifer eziry- 

 teines Owen, which here exhibits great variations of form. 

 Shells of the last named species are rarely found at the quarry, 

 and only in one or two places, not in the rock but in the soil above 

 composed of disintegrated rock. They are quite abundant in 

 the upper " soapstone " from the intake. It is not probable that 

 any had been unearthed at the time of the publication of the 

 Geology of Wisconsin. They are distinguished by clearly marked 

 lines of fine striation. 



The writers have not attempted the correlation of the Mil- 

 waukee fauna with the faunas of other localities, but leave that 

 interesting task to more competent hands. The Spirifers of the 

 list, however (S. towaensis Owen = 5. pennatus Owen ; 5. asper 

 Hall ; S. euryteines Owen = 5. parryanus Hall = 6". capax Hall ; 

 and 5. subvaricosus H. & Wh.) show an obvious relation to cer- 

 tain Devonian faunas of Iowa. It is proper to state that the shell 

 here identified as 5. subvaricosus H. & Wh. was by Mr. Schuchert 

 considered to be a primitive form of 6". bimesialis H., another 

 Iowa species. Professor Whitfield, however, considers the iden- 

 tification as 5. subvaricosus to be correct. Specimens of the shell 

 from B 2, in which the beak has been ground down, seem to 

 show a median septum. So do the casts in B. The latter, how- 

 ever, do not generally show the strong plication of fold and 

 sinus, and such have been identified as Delthyris co?isobrina, D'Orb. 

 (=S. ziczac Hall.) There is in the list a little Rhynchonella, 

 identified as R. contracta, var. saxatilis Hall, which, if properly 

 named, belongs also to the Rockford and High Point faunas. 

 The Milwaukee specimens of Schizophoria striatula Schl. (= OrtJiis 

 imprcssa Hall) are a form with a wide and not very deep sinus. 

 Occasional forms are found resembling Schizophoria tullicnsis 

 Vanuxem, and 5. macfarla?ii Meek. 



